1. Field of the Invention
The present invention relates to a power supply apparatus for use with a multiple-unit system composed of a plurality of electronic units such as a plurality of display monitors.
2. Description of the Prior Art
There is known a multiple-unit image display system composed of a plurality of display monitors for jointly providing a single screen for displaying images. Such a multiple-unit image display system will hereinafter be referred to as a "multibillboard system".
FIG. 1 of the accompanying drawings shows a conventional multibillboard system. The multibillboard system, generally designated by the reference numeral 1, comprises a matrix of connected display monitors 2A, 2B, 2C, 2D, . . . , with four display monitors in each vertical column and four display monitors in each horizontal row. Each of the display monitors 2A, 2B, 2C, 2D, . . . is supplied with an image signal depending on the two-dimensional position of the display monitor in the multibillboard system.
In the illustrated multibillboard system, the total of sixteen display monitors 2A, 2B, 2C, 2D, . . . jointly provide a single large image screen for displaying images thereon.
When all the display monitors 2A, 2B, 2C, 2D, . . . are energized simultaneously by a power supply apparatus, a large rush current flows from the power supply apparatus to the multibillboard system. If the number of connected display monitors 2A, 2B, 2C, 2D, . . . increases, then an overcurrent protector or a circuit breaker associated with the multibillboard system may be actuated when the rush current is supplied from the power supply apparatus. When the circuit breaker is actuated, the multibillboard system cannot readily be energized or switched into operation.
One solution would be to turn on the display monitors 2A, 2B, 2C, 2D, . . . successively one by one. However, such a process of energizing the multibillboard system would be tedious and time-consuming, making the multibillboard system inconvenient to use.